#define  _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
int main()
{
	
	int t,i;
	double f=0;
	scanf("%d", &t);
	for ( i = 1; i <=t; i++)
	{
		f = f + 1.0 / i;
	}
	printf("f(%d)=%f", t, f);
	return 0;
}